2 - Paeds - CVS - Atrial Septal Defect (ASD)

Question 1

2 types?

Answer 1

secundum - 80%
Partial AVSD (primum ASD/pAVSD)

Question 2

difference between secundum and primum

Answer 2

primum -> defet in AV septum, characterised by:

• inter-atrial communication between bottom end of atrial septum and the AV valves
• abnormal AV valves with a left AV valve which has three leaflets and regurgitates

secundum -> defect in centre of atrial septum involving foramen ovale

Question 3

symptoms?

Answer 3

commonly aSx

• recurrent chest infections/wheeze
• arrhythmias (4th decade on)

Question 4

signs? specific to pAVSD?

Answer 4

ej sys murmur best at upper left sternal edge - due to incr fow across pulm valve due to shunt

HS2 - fixed and widely split

with pAVSD - apical pan sys murmur from AV valve regurgitation

Question 5

3 Ix? most important?

Answer 5

CXR
ECG
ECho!!!11

Question 6

what to look for on CXR

Answer 6

cardiomegaly, enlarged pulm arteries and increased pulm vascular markings

Question 7

what to look for on ECG

Answer 7

secundum > partial RBBB common, R axis dev due to RV enlargement

pAVSD > superior QRS axis due to defect in middle part of heart where AVN is, displaced node conducts to ventricles superiorly -> abnormal axis

Question 8

mgmt ?

secundum?

Answer 8

sign ASD - causing RV dilatation -> needs Tx

sASD > cardiac catheter - insert occlusion device

pAVSD - surgical correction, usually 3-5y to prevent RHF and arrhythmias later in life